1. Field of the Invention
The present invention relates to a method for controlling an internal combustion engine so as to perform ignition control or fuel control, wherein a signal is supplied to an external device at a desired rotational position of an internal combustion engine.
2. Description of the Related Art
Various electronic control apparatuses for an internal combustion engine are known. In one such apparatus a reference position sensor is used to produce a reference signal at a known rotational position of an internal combustion engine, a rotational angle sensor is used to produce angular signals at predetermined crank angle intervals of the internal combustion engine, and a control member is used such as a microcomputer having a time counting device. In this apparatus, only a limited number of angular signals are obtained from the rotational angle sensor per each revolution of the internal combustion engine. Therefore, each angular signal must be correctly interpolated to allow the production of correct outputs at desired rotational positions of the engine even when there are variations in the engine speed or the rotational speed of the engine, which are inherent in the internal combustion engine. However, when there are variations in the rotational speed of the internal combustion engine or when the engine is in a transient state such as acceleration or deceleration, this method cannot achieve a correct control, as explained in detail later.